Injection molding of micro-porous titanium alloy with space holder technique

Abstract

The powder space holder (PSH) and powder injection molding (PIM) methods have an industrial competitive advantage because they are capable of the net-shape production of micro-sized porous parts. In this study, micro-porous Ti6Al4V alloy (Ti64) parts were produced by the PSH-PIM process. Ti64 alloy powder and spherical polymethylmethacrylate (PMMA) particles were used as a space holder material. After molding, binder debinding was performed by thermal method under inert gas. Debinded samples were sintered at 1250A degrees C for 60 min in a vacuum (10(-4) Pa). Metallographic studies were conducted to determine densification and the corresponding microstructural changes. The surface of sintered samples was examined by SEM. The compressive stress and elastic modulus of the micro-porous Ti64 samples were determined. The effects of fraction of PMMA on the properties of sintered micro-porous Ti64 alloy samples were investigated. It was shown that the fraction of PMMA could be controlled to affect the properties of the Ti alloy.